High storage capacity is one of the main aims of optical storage technology. To realize high storage density, the key and efficient way is to obtain optical storage materials capable of recording information in high density by means of laser beam with short wavelength. In the present work, the preparation and blue-shift phenomenon of optical absorption of the composite materials coated-codoped with nanosized metal and azo-dye were reported. It was found that, due to the specific structure of the composite film, the absorption maximum of azo-dye methyl orange (MO) shifted about 23 nm towards shorter wavelength region and the heat stability of the composite film was improved compared with that of MO in polyvinyl alcohol film only. The samples were characterized by TEM, SPM, UV-vis and TGA. The structural model for the coating-codoping was described. The mechanism of blue-shift was discussed. These results indicate that, the composite film which absorbed in blue-violet region (400～450 nm), and was capable of matching the laser (GaN) beam, has potential as a new type of optical recording materials.

Key words: nanosized metal, azo-dye, coating-codoping, absorption blue-shift, optical storage material